/*
 * Copyright 2010-2015 JetBrains s.r.o.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.jetbrains.kotlin.descriptors

import org.jetbrains.kotlin.types.KotlinType
import org.jetbrains.kotlin.types.TypeConstructor

interface SupertypeLoopChecker {
    fun findLoopsInSupertypesAndDisconnect(
            currentTypeConstructor: TypeConstructor,
            superTypes: Collection<KotlinType>,
            neighbors: (TypeConstructor) -> Iterable<KotlinType>,
            reportLoop: (KotlinType) -> Unit
    ): Collection<KotlinType>

    object EMPTY : SupertypeLoopChecker {
        override fun findLoopsInSupertypesAndDisconnect(
                currentTypeConstructor: TypeConstructor,
                superTypes: Collection<KotlinType>,
                neighbors: (TypeConstructor) -> Iterable<KotlinType>,
                reportLoop: (KotlinType) -> Unit): Collection<KotlinType> = superTypes
    }
}
